I-73 math just doesn’t add up

Supporters of construction of I-73 continue to claim that it will produce “29,000 jobs.” The Chmura “Economic Impact of I-73 in South Carolina” report, commissioned by the North Eastern Strategic Alliance appears to be the source of that claim.

Supporters of construction of I-73 continue to claim that it will produce “29,000 jobs.” The Chmura “Economic Impact of I-73 in South Carolina” report, commissioned by the North Eastern Strategic Alliance appears to be the source of that claim.

I have challenged the accuracy of that report in the past, but thinking that I may have made some mistake in my critique, I did a little bit more research. Chmura had claimed that I-73 would save between one to two hours travel time, despite the federal Environmental Impact Statement projecting 20 to 30 minutes. Using the same type of calculations that resulted in Chmura projecting a 7.1 percent increase in tourism, the shorter time saved results in a prediction of just over 1.9 percent increase due to travel time savings.

Chmura then compounded that mistake by applying her 7.1 percent increase to the entire annual tourist volume in calculating the increase in tourist spending. Only 80 percent of Myrtle Beach tourists visit by car, and only 70 percent of them arrive by I-95. An even smaller subset of those I-95 travelers would use all or any part of I-73.

I dug a little deeper and found what the 2006 to 2011 average annual daily traffic counts have been at the various SCDOT traffic count stations along the routes S.C. 38, U.S. 501 and S.C. 22 that I-73 would parallel.

It is always a difficult task to separate daily commuter traffic from the sort of tourist traffic that I-73 is supposed to attract. There are two isolated, rural segments along the S.C. 38/U.S. 501/S.C. 22 route that have averaged 5,300 daily traffic or less over the 2006 to 2011 period. Even some of that traffic may be local commuter, but let’s be generous and assume that this was totally tourist traffic. Using Chmura’s assumptions of four visitors per vehicle, and only counting these tourists once (the traffic numbers are for both directions), I calculate the annual tourist volume that could potentially save travel time on I-73 is 3,869,000 visitors per year.

Chmura then cited Myrtle Beach Area Chamber of Commerce surveys that said the average tourist stayed for 5.6 nights and spent $98 per day in Myrtle Beach. Using these numbers, multiplied by a 1.93 percent increase in the 3,869,000 tourists that might save time on I-73, we now see that I-73 might realistically result in an increase in direct tourist spending in the Myrtle Beach area of $40,979,829 per year (in 2009 dollars – the year of the chamber survey).

This is less than 7 percent of the $592,264,960 (in 2009 dollars) additional tourist expenditure Chmura and the boosters claim will be produced by I-73. That means that their claimed 18,856 total new jobs resulting from an increase in tourism generated by I-73, consisting of 12,669 direct jobs within the Myrtle Beach tourism industry and 6,187 jobs created by the “ripple spending effects” around South Carolina are more likely to be just 1,305 total.

I have engaged in what may be termed “forensic arithmetic” in trying to figure out how the I-73 boosters arrived at their outlandish claims, and have recalculated using some more realistic input data. Any time anyone from the chamber, NESA, Grand Strand Business Alliance, SCDOT or any other I-73 booster wants to challenge my calculations, drop me a line or give me a call, and we can meet and go over my math and your math.